Niue, a sovereign state in free association with New Zealand, uses two official legal tender currencies. The New Zealand Dollar is the circulation currency for daily transactions, while the government also authorises legal tender coins in the Niue Dollar currency for collector's purposes.
A number of mints issue a large variety of commemorative, bullion and collector coins under the authority of Niue. These coins are dedicated to historical or general popular culture themes not related to Niue itself. Many of them are in standard bullion sizes - typically, one ounce of silver (abbreviated as 1 oz Ag, where "Ag" comes from the Latin word for silver, Argentum). Many of these feature various animals.
This coin is part of a series by the Mint of Poland dedicated to butterflies, and depicts a Papilio Machaon (Swallowtail) butterfly.
The Mint says about it:
"The fourth issue in the captivating Butterflies series of silver coins bears the title “Old World Swallowtail” and is dedicated to a strikingly coloured butterfly of the family Papilionidae found in a number of locations including Europe, Asia and China. This butterfly got its name due to its large yellow and black wings with a tail resembling that of a swallow. With a wingspan of around 10 cm, they are remarkable for excellent fast flying abilities. Thanks to the pad printing technique the image on the coin displays the genuine colours of the butterfly. To the right of the image, there is the inscription denoting the Latin name of the insect." | 
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